With the aim of producing Biofertilizers, soil samples were taken from three types of land use (TUT): TUT Pasto E (organic fertilization), TUT Bosque N (unintervened area), and TUT Melón (under conventional management), located in the organic waste recycling unit "Germán Lugo" in Coro, Falcón state. From these samples, isolations were made to determine the microbial richness with biofertilizing power and the effect they had on the quantity and diversity of bacteria found. The isolations were carried out in three semi-selective media: YMA (for symbiotic nitrogen fixers FNS), PK (for phosphorus solubilizers SF), and Ashby (for free-living nitrogen fixers FNVL). Despite the low values of organic matter, nitrogen, and phosphorus obtained in the soil analysis, the quantity and diversity of FNVL and FNS bacterial colonies were good, found in all TUTs. In contrast, SF bacteria were found only in TUT Pasto E. Six types of nitrogen-fixing bacterial strains were selected and inoculated in trays with tomato seedlings to determine their stimulating power. These strains were compared with a commercial biofertilizer, and the result showed that treatment 4 (T4) (Pasto E 2) produced the best results, even surpassing the commercial biofertilizer and significantly differing from the control (T7). Treatments T2, T3, and T6 also responded well and showed potential as biofertilizers.
